ODD ygons VEN Filling WINklawonn/computergraphics/e-buch/Folien/... · Filling pol ygons In order...
64
c Filling polygons How to determine the interior of a polygon: Odd parity rule: A point lies inside a polygon if a line starting at the point intersects with an odd number of edges of the polygon. Java 2D provides the method g2d.fill(s); for filling a Shape s. In order to apply the odd parity rule for filling, f.e. a GeneralPath gp, gp.setWindingRule(GeneralPath.WIND_EVEN_ODD); is needed. Computer Graphics: Areas, text and colours – p.1/64
Transcript of ODD ygons VEN Filling WINklawonn/computergraphics/e-buch/Folien/... · Filling pol ygons In order...
c
�
Fill
ing
po
lyg
on
s
How
tode
term
ine
the
inte
rior
ofa
poly
gon:
Od
dp
arit
yru
le:
Apo
intl
ies
insi
dea
poly
gon
ifa
line
star
ting
atth
epo
inti
nter
sect
sw
ithan
odd
num
ber
ofed
ges
ofth
epo
lygo
n.
Java
2Dpr
ovid
esth
em
etho
dg2d.fill(s);
for
fillin
gaShape
s.
Inor
der
toap
ply
the
odd
parit
yru
lefo
rfil
ling,
f.e.a
GeneralPath
gp
,
gp.setWindingRule(GeneralPath.WIND_EVEN_ODD);
isne
eded
.
Com
pute
rG
raph
ics:
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as,t
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ndco
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s–
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64
c
�
Od
dp
arit
yru
le
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xt)
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xt)
4 (e
xt)
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pute
rG
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ics:
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ndco
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s–
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64
c
�
Fill
ing
po
lyg
on
s
Inor
der
tofil
lapo
lygo
nw
itha
give
nco
lour
,asc
anlin
eis
used
for
each
� -val
uean
dth
epo
ints
tobe
draw
nal
ong
the
scan
line
are
dete
rmin
ed.
1.D
eter
min
eal
lint
erse
ctio
npo
ints
ofth
esc
anlin
ew
ithal
lpol
ygon
edge
s.
2.S
ortt
hein
ters
ectio
npo
ints
inin
crea
sing
orde
rw
.r.t.
thei
r� -c
oord
inat
es.
Com
pute
rG
raph
ics:
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ndco
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s–
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c
�
Fill
ing
po
lyg
on
s
3.A
pply
the
odd
parit
yru
leto
dete
rmin
ew
hich
poin
tslie
insi
deth
epo
lygo
n.
�
Sta
rtfr
omth
ele
ftw
ithev
enpa
rity.
�
Jum
pto
the
first
inte
rsec
tion
poin
toft
hesc
anlin
ew
ithth
epo
lygo
n,(c
hang
eth
epa
rity
tood
dan
d)dr
awal
lpix
elun
tilth
ene
xtin
ters
ectio
npo
inti
sre
ache
d.
�
The
nsk
ipth
epi
xels
until
the
next
inte
rsec
tion
poin
tis
reac
hed.
Dra
wal
lpix
elun
tilth
ene
xtin
ters
ectio
npo
inti
sre
ache
d.
�
�
� Com
pute
rG
raph
ics:
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ndco
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s–
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c
�
Fill
ing
po
lyg
on
s
Alia
sing
effe
ctoc
curr
ing
whe
nth
inpo
lygo
nsar
efil
led:
Com
pute
rG
raph
ics:
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ndco
lour
s–
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64
c
�
Fill
ing
clo
sed
curv
es
�
Fill
ing
circ
les,
ellip
ses,
arcs
ofci
rcle
sor
ellip
ses
isdo
nein
the
sam
ew
ay.
�
Sym
met
rypr
oper
ties
shou
ldbe
expl
oite
dto
redu
ceth
eca
lcul
atio
ns.
�
Fill
ing
ofar
bitr
ary
clos
edcu
rves
isal
sodo
nein
the
sam
ew
ay.
�
Whe
nth
ebo
unda
ryof
anar
eais
draw
nus
ing
antia
liasi
ng,t
hepi
xels
belo
ngin
gto
the
edge
are
nolo
nger
uniq
uely
defin
ed.
Com
pute
rG
raph
ics:
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ndco
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c
�
Text
ure
s
Usi
nga
text
ure
once
orm
ore
than
once
for
fillin
gan
area
.
An
anch
or
mus
tbe
spec
ified
.T
hean
chor
defin
esa
star
ting
poin
tfro
mw
hich
the
text
ure
isla
idlik
etil
es.
Com
pute
rG
raph
ics:
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ndco
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c
�
Bu
ffer
edIm
ages
ABufferedImage
isan
imag
ein
the
mem
ory
�
whi
chca
nbe
draw
non
and
�
whi
chca
nal
sobe
draw
non
anImage
.
BufferedImage
bi
=new
BufferedImage(width,height,
BufferedImage.TYPE_INT_RGB);
Graphics2D
g2dbi
=bi.createGraphics();
Com
pute
rG
raph
ics:
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ndco
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c
�
Bu
ffer
edIm
ages
g2dbi.draw(...);
g2dbi.fill(...)
g2d.drawImage(bi,xpos,ypos,null);
drawImage
can
beus
edto
draw
ona
win
dow
oron
aBufferedImage
.
Com
pute
rG
raph
ics:
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64
c
�
Do
ub
leB
uff
erin
g
Prin
cipl
eof
doub
lebu
fferin
g:U
se
�
aBufferedImage
theBackground
cont
aini
ngth
est
atic
back
grou
ndth
atw
illno
tcha
nge,
�
aBufferedImage
theImage
onw
hich
afte
rea
chst
epof
anim
atio
nfir
stth
etheBackground
isdr
awn
and
then
the
anim
ated
obje
cts,
and
�
aG
raph
ics2
Dob
ject
(as
usua
lg2d
)w
hich
isus
edfo
rdr
awin
gtheImage
onth
ew
indo
w.
Com
pute
rG
raph
ics:
Are
as,t
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ndco
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s–
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/64
c
�
Do
ub
leB
uff
erin
g
Win
dow
tobe
draw
nup
on(BufferedImageDrawer
):A
ttrib
utes
:public
BufferedImage
bi;
public
Graphics2D
g2dbi;
Met
hods
:public
void
paint(Graphics
g)
{update(g);
} public
void
update(Graphics
g)
{g2d
=(Graphics2D)
g;
g2d.drawImage(bi,0,0,null);
}C
ompu
ter
Gra
phic
s:A
reas
,tex
tand
colo
urs
–p.
11/6
4
c
�
Do
ub
leB
uff
erin
g
Impl
emen
tatio
nof
thes
em
etho
dsin
the
clas
sBufferedImageDrawer
.N
eces
sary
step
s:
�
Com
puta
tions
take
plac
ein
acl
ass
exte
ndin
gth
eJa
vacl
assTimerTask
.
�
The
run
met
hod
inth
iscl
ass
cont
ains
the
com
puta
tions
that
wer
epr
evio
usly
done
inth
eF
OR
-loop
ofth
epaint
-Met
hod.
�
Dra
win
gis
notd
one
with
theGraphics2D
obje
ctof
thepaint
met
hod
ofth
ew
indo
w,b
utw
ithth
eGraphics2D
obje
ctof
the
corr
espo
ndin
gBufferedImage
bi
.
Com
pute
rG
raph
ics:
Are
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ndco
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s–
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/64
c
�
Do
ub
leB
uff
erin
g
�
Inst
ead
ofcl
earin
gth
edr
awin
gar
ea(p
aint
ing
the
BufferedImage
bi
whi
te)
inea
chst
ep,a
noth
erBufferedImage
cont
aini
ngth
eba
ckgr
ound
isdr
awn
onbi
each
step
.
�
The
repaint
met
hod
ofth
eBufferedImageDrawer
mus
tbe
calle
dat
the
end
ofth
erun
met
hod.
Com
pute
rG
raph
ics:
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ndco
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c
�
�
Do
ub
leB
uff
erin
g
Initi
alis
atio
nsta
kepl
ace
inth
emain
met
hod
and
inth
eco
nstr
ucto
rof
the
spec
ific
clas
s.
The
run
met
hod,
inw
hich
the
sequ
ence
ofim
ages
isco
mpu
ted
and
whi
chin
itiat
esdr
awin
g,is
calle
dre
peat
edly
by
Timer
t=
new
Timer();
t.scheduleAtFixedRate(dbce,0,delay);
(see
DoubleBufferingClockExample.java
)
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
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/64
c
�
Lo
adin
gim
ages
Usi
ng
Image
theImage;
theImage
=new
javax.swing.ImageIcon(
"filename.jpg").getImage();
anim
age
can
belo
aded
.T
his
imag
eca
nbe
draw
nat
the
posi
tion
�
���
��
usin
g
g2d.drawImage(theImage,x,y,null);
g2d
isth
eG
raph
ics2
Dob
ject
ofth
ew
indo
wor
ofa
BufferedImages
.
Com
pute
rG
raph
ics:
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as,t
exta
ndco
lour
s–
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/64
c
�
Sav
ing
imag
es
�
Gen
erat
eaBufferedImage
theImage
.
�
Gen
erat
eth
eco
rres
pond
ing
Gra
phic
s2D
obje
ct:
Graphics2D
g2dImage
=theImage.createGraphics();
�
Dra
wth
eim
age
(usi
ngg2dImage
).
�
Gen
erat
eaFileOutputStream
fos
for
the
file
inw
hich
the
imag
esh
ould
best
ored
.
�
Sto
reth
eim
age
usin
gth
eJPEGImageEncoder
.
(see
ImageSavingExample.java
)
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
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/64
c
�
Sav
ing
imag
es
try
{FileOutputStream
fos
=new
FileOutputStream("test.jpg");
JPEGImageEncoder
jie
=JPEGCodec.createJPEGEncoder(fos);
jie.encode(theImage);
} catch
(Exception
e)
{System.out.println(e);
}
Com
pute
rG
raph
ics:
Are
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exta
ndco
lour
s–
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c
�
Text
ure
sin
Java
2D
Usi
nga
text
uretheImage
(for
inst
ance
,obt
aine
dfr
omJP
EG
imag
e)on
ceto
filla
Shape
s:
Shape
clipShape
=g2d.getClip();
g2d.setClip(s);
g2d.drawImage(theImage,50,50,null);
g2d.setClip(clipShape);
Com
pute
rG
raph
ics:
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exta
ndco
lour
s–
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/64
c
�
Text
ure
sin
Java
2D
Fill
ing
aShape
sre
peat
edly
with
ate
xtur
etheImage
give
nas
aJP
EG
imag
e:
�
The
text
ure
mus
tbe
load
edan
ddr
awn
onto
aBufferedImage
buffImage
.
�
Gen
erat
ea
TexturePaint
tp
=new
TexturePaint(buffImage,
new
Rectangle(0,0,
buffImage.getWidth(),
buffImage.getHeight()));
g2d.setPaint(tp);
g2d.fill(s);
Com
pute
rG
raph
ics:
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ndco
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s–
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/64
c
�
Text
Lette
rsan
dsy
mbo
lsca
nbe
save
din
two
form
s:
�
As
abi
tmap
(pix
elm
atrix
)or
�
inth
efo
rmof
poly
gons
orcu
rves
.
Whe
nbi
tmap
sar
eus
ed,e
ach
sym
bolm
ustb
est
ored
inal
lsiz
esan
dal
lsty
les
(nor
mal
,bol
dfac
e,ita
lic,
bold
face
italic
).A
repr
esen
tatio
nas
poly
gons
orcu
rves
issc
alab
le.
Diff
eren
tsiz
esca
nbe
com
pute
dfr
omon
ere
pres
enta
tion
ofth
ele
tter.
Com
pute
rG
raph
ics:
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ndco
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s–
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c
�
Text
An
old,
sim
ple,
butn
otve
ryni
cete
chni
que
for
gene
ratin
gita
lican
dbo
ldfa
cesy
mbo
lsfr
ombi
tmap
s:
norm
alita
licb
old
face
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
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/64
c
�
Text
inJa
va2D
Dra
win
g/w
ritin
gte
xt:
g2d.drawString("text",posx,posy);
Cho
osin
gth
efo
nt:
Font
f=
new
Font("type",Font.STYLE,size);
Ava
ilabl
efo
nts
(for
type
):Font[]
fl
=GraphicsEnvironment.
getLocalGraphicsEnvironment(
).getAllFonts();
for
(int
i=0;
i<fl.length;
i++)
{System.out.println(fl[i].getName());
}C
ompu
ter
Gra
phic
s:A
reas
,tex
tand
colo
urs
–p.
22/6
4
c
�
Text
Val
ues
forSTYLE
:
�
PLAIN
(nor
mal
)
�
ITALIC
(ital
ic/s
lant
ed)
�
BOLD
(bol
dfac
e)
�
ITALIC
|BOLD
(ital
ican
dbo
ldfa
ce)
size
spec
ifies
the
size
ofth
efo
nt(in
the
unit
pt,n
otin
pixe
ls).
Afte
rca
lling
the
met
hodg2d.setFont(f)
,drawString
isus
ing
the
fontf
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
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/64
c
�
Mo
dif
yin
gfo
nts
App
lyin
ga
tran
sfor
mat
ionaffTrans
toth
ew
hole
font
:Font
transformedFont
=f.deriveFont(affTrans);
Tran
sfor
mat
ion
ofsi
ngle
sym
bols
ofa
strin
gs
:FontRenderContext
frc
=g2d.getFontRenderContext();
GlyphVector
gv=
f.createGlyphVector(frc,s);
Com
pute
rG
raph
ics:
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as,t
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ndco
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s–
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/64
c
�
Mo
dif
yin
gsy
mb
ols
Point2D
p=
gv.getGlyphPosition(i);
Shape
glyph
=gv.getGlyphOutline(i);
Shape
transGlyph
=at.createTransformedShape(glyph);
g2d.fill(transfGlyph);
(see
TextExample.java
)
Com
pute
rG
raph
ics:
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ndco
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�
Gre
y&
colo
ur
imag
es
Inte
nsi
tyle
vels
for
gre
yo
rco
lou
rva
lues
:
Pix
els
cann
otbe
only
blac
kor
whi
te.
Inst
ead
afin
itenu
mbe
rof
inte
nsity
leve
ls(g
rey-
leve
lsor
inte
nsity
leve
lsfo
rco
lour
s)is
avai
labl
e.
The
hum
anpe
rcep
tion
oflig
htin
tens
ities
ism
ainl
ya
rela
tive
one.
A60
-wat
tlig
htbu
lbis
muc
hbr
ight
erin
com
paris
onto
a20
-wat
tlig
htbu
lbth
ana
100-
wat
tlig
htbu
lbin
com
paris
onto
a60
-wat
tlig
htbu
lb.
Com
pute
rG
raph
ics:
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ndco
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s–
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c
�
Gre
y&
colo
ur
imag
es
The
inte
nsity
leve
lssh
ould
noti
ncre
ase
linea
rly,b
utex
pone
ntia
lly.
Sta
rtin
gfr
omth
elo
wes
tint
ensi
ty((
alm
ost)
blac
kfo
rgr
eyva
lues
)
��� ,th
ele
vels
shou
ldbe
chos
enac
cord
ing
to
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�
�
upto
am
axim
umin
tens
ity
���
���� � .
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pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.27
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c
�
Gre
y&
colo
ur
imag
es
The
aver
age
hum
anvi
sion
syst
emis
able
todi
stin
guis
hbe
twee
ngr
ey-le
vels
whe
nth
eydi
ffer
byat
leas
t1%
,i.e
.,if
��� �
��
hold
s.
Ass
umin
ga
max
imum
inte
nsity
���
�� an
da
min
imum
inte
nsity
��� ,de
pend
ing
onth
eou
tput
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ce,f
rom
� �
���� �
�� �
follo
ws
that
mor
eth
an
��
���� � ��
����
� �
���
grey
-leve
lsw
illno
tcon
trib
ute
tobe
tter
imag
equ
ality
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.28
/64
c
�
Gre
y&
colo
ur
imag
es
Med
ium
���
(ca.
)M
ax.n
o.of
grey
-leve
ls
mon
itor
0.00
5-0.
025
372-
533
new
spap
er0.
123
2ph
oto
0.01
464
slid
e0.
001
695
Ifan
outp
utde
vice
allo
ws
only
bina
rypi
xels
,for
inst
ance
abl
ack-
and-
whi
tela
ser
prin
ter,
diffe
rent
inte
nsity
leve
lsca
nbe
repr
esen
ted
for
the
pric
eof
alo
wer
reso
lutio
n.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.29
/64
c
�
Hal
fto
nin
g
Com
bini
ng
�
�� -P
ixel
toa
larg
erpi
xel,
5in
tens
ityle
vels
can
bere
pres
ente
d.F
or
�
��
pixe
ls10
,for
��
�
pixe
ls
��
�� .
�
The
coar
sene
dre
solu
tion
mus
tstil
lbe
high
enou
ghso
that
the
pixe
lras
ter
isno
tim
med
iate
lyvi
sibl
e.
�
The
�
pixe
lsfo
rth
egr
ey-le
vel
�
shou
ldbe
chos
enin
such
aw
ayth
atth
eyar
ene
ighb
ourin
gpi
xels
and
they
dono
tfor
ma
regu
lar
patte
rnlik
ea
line.
Oth
erw
ise,
this
mig
htin
trod
uce
new
visu
alar
tifac
tslik
est
ripes
inan
area
ofid
entic
alin
tens
ityva
lues
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.30
/64
c
�
Hal
fto
nin
g
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.31
/64
c
�
Hal
fto
nin
g
Rep
rese
ntat
ion
bydi
ther
mat
rices
:
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�
�
�
�
�
�
���
��
�
�
�
�
�
�
�
�
�
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.32
/64
c
�
Hal
fto
nin
g
Asi
mila
rre
finem
entt
echn
ique
can
beap
plie
dw
hen
nonb
inar
yin
tens
ityle
vels
are
avai
labl
ein
the
first
plac
e.F
orin
stan
ce,u
sing
2
� 2pi
xelm
atric
esw
here
each
pixe
lcan
have
four
diffe
rent
inte
nsity
leve
lsyi
elds
13po
ssib
lein
tens
ityle
vels
:
� �
�
�
�
�
� � �
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�
�
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�
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�
�
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�
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�
�
�
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�
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�
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�
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� �
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.33
/64
c
�
Co
lou
rm
od
els
�
The
oret
ical
desc
riptio
nof
aco
lour
:In
tens
ities
inth
eco
lour
spec
trum
.
�
Mai
nch
arac
teris
tics
ofa
colo
ur:
�
Hu
eco
rres
pond
ing
toth
edo
min
antw
avel
engt
hin
the
spec
trum
ofth
eco
lour
,
�
Sat
ura
tio
nor
purit
yw
hich
ishi
ghw
hen
the
spec
trum
cons
ists
ofa
narr
owpe
akat
the
dom
inan
twav
elen
gth,
and
whi
chis
low
for
afla
tter
spec
trum
,and
�
Inte
nsity
orlig
htn
ess
depe
ndin
gon
the
ener
gyof
the
spec
trum
.T
hehi
gher
the
ener
gyof
the
sing
lefr
eque
ncie
s,th
ehi
gher
isth
ein
tens
ity.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.34
/64
c
�
Co
lou
rm
od
els
visi
ble
rang
e:ca
.400
nm(v
iole
t)to
700n
m(r
ed)
Hig
hsa
tura
tion:
Hig
hco
ncen
trat
ion
inth
esp
ectr
um.
400
700
wavelength [nm]
energy
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.35
/64
c
�
Co
lou
rm
od
els
Low
satu
ratio
n:W
ide-
spre
adsp
ectr
um.
400
700
wavelength [nm]
energy
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.36
/64
c
�
Ad
dit
ive/
sub
trac
tive
colo
ur
mo
del
s
�
Add
itive
colo
urm
odel
sfo
rlig
ht:
�
Bla
ck(d
ark)
back
grou
nd
�
red+
gree
n+bl
ueyi
elds
whi
te.
�
Exa
mpl
e:m
onito
r
�
subt
ract
ive
colo
urm
odel
for
colo
urs:
�
Whi
te(li
ght)
back
grou
nd
�
red+
gree
n+bl
ueyi
elds
blac
k/da
rkbr
own.
�
Exa
mpl
e:pr
inte
r
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.37
/64
c
�
Th
eR
GB
mo
del
Sta
ndar
dco
lour
mod
elfo
rm
onito
rs:
RG
Bm
od
el.
Eac
hco
lour
isco
mpo
sed
ofth
eth
ree
prim
ary
colo
urs
red,
gree
nan
dbl
ue.
colo
ur
�
��
����
��
�� ��
whe
re
� ���
��
� � �
� .
�
� �
� �
��
corr
espo
nds
tobl
ack,
�
� �
� �
��
isw
hite
,
�
���
���
��
defin
esa
light
eror
dark
ergr
ey,d
epen
ding
onth
ech
oice
of
� ,
�
� �
� �
��en
code
sre
d,
�
� �
� �
��
gree
nan
d
�
� �
� �
��
blue
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.38
/64
c
�
Th
eR
GB
mo
del
Usu
ally
,for
the
codi
ngof
the
inte
nsity
ofa
colo
ur,o
neby
teis
used
,so
that
each
ofth
epr
imar
yco
lour
sha
s25
6di
ffere
ntle
vels
ofin
tens
ity.
InJa
va2D
,aco
lour
can
bede
fined
usin
gth
eco
nstr
ucto
rs
�
new
Color(float
r,
float
g,
float
b)
(r,g,b
�� � �
� )or
�
new
Color(int
r,
int
g,
int
b)
(r,g,b
��
� �
� �
�
�
��
���
� ).
Not
ever
yco
lour
can
bere
pres
ente
dw
ithin
the
RG
Bm
odel
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.39
/64
c
�
Th
eC
IEX
YZ
mo
del
For
this
reas
on,t
heC
omm
issi
onIn
tern
atio
nale
del’É
clai
rage
(CIE
)in
trod
uced
am
odel
with
thre
ear
tifici
alco
lour
s
� ,
� and
� whi
chca
nre
pres
enta
nyot
her
colo
ur.
colo
ur
�
��
��
��
����
��
whe
re
���
� ��
�� � �
� .
How
ever
,find
ing
suita
ble
com
bina
tions
ofth
eth
ree
artifi
cial
colo
urs
tom
odel
ade
sire
dco
lour
isno
tver
yin
tuiti
ve,s
oth
atth
eC
IEX
YZ
mod
elis
seld
omus
ed.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.40
/64
c
�
Th
eC
MY
mo
del
The
subt
ract
ive
CM
Ym
odel
isth
edu
alto
the
RG
Bm
odel
and
isus
edfo
rpr
inte
rsan
dpl
otte
rs
The
prim
ary
colo
urs
are
cyan
,mag
enta
and
yello
w.
Red
Green
Blue
B la ck
Yellow
Cya
n
Mag
enta
Wh it e
�
� � �
�����
� � �
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.41
/64
c
�
Th
eC
MY
Km
od
el
The
CM
YK
mod
elus
esbl
ack
(K:k
ey)
asa
four
thco
lour
.
The
CM
YK
mod
elis
the
stan
dard
colo
urm
odel
for
prin
ters
yiel
ding
bette
rco
lour
sth
anth
eC
MY
mod
el.
CM
Y
� CM
YK
���
�
�� ��
� �
� �
��
� �
�
� �
�
� �
�
� �
�
���
�
� �
�
� Atl
east
one
ofth
efo
urva
lues
� �
� �
� �
� is0.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.42
/64
c
�
Th
eY
IQm
od
el
The
YIQ
mod
elis
notb
ased
onth
ree
prim
ary
colo
urs
asin
the
RG
Ban
dth
eC
MY
mod
el,b
utit
uses
the
thre
eco
mpo
nent
s
lum
inan
ce
� and
chro
mat
icit
y
� ,
�
tode
fine
aco
lour
.
Use
din
the
Am
eric
anN
TS
Cte
levi
sion
norm
.
Col
our
� grey
imag
e:U
seon
lyth
e
� -val
ue.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.43
/64
c
�
Th
eY
IQm
od
el
�
� � �
��
� �
���
� �
���
� �
���
� �
����
� �
����
� �
���
� �
����
� �
���
� �
���
��
� � �
Adv
anta
ges
ofth
eY
IQm
odel
:
�
Eas
ytr
ansf
orm
atio
nfr
omco
lour
sto
grey
-leve
ls,
dete
rmin
edon
lyby
the
� -val
ue.
�
Hel
pful
whe
nco
mpu
ter
mon
itors
with
diffe
rent
brig
htne
sssh
ould
bead
just
ed,s
oth
atth
eco
lour
sth
eysh
owar
em
ore
orle
ssth
esa
me
for
iden
tical
RG
Bva
lues
.M
uch
easi
erto
adju
ston
lyth
e
� -val
ueth
anto
adju
stth
eth
ree
valu
es
� ,
� and
�
atth
esa
me
time.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.44
/64
c
�
Th
eH
SV
mo
del
Par
amet
ers:
�
hue
�
satu
ratio
n
�
valu
e
Mod
elin
the
form
ofan
upsi
dedo
wn
pyra
mid
:
�
Tip
ofth
epy
ram
id:
blac
k.
�
The
hue
� isgi
ven
byth
ean
gle.
�
Sat
urat
ion
(
� ):0
inth
em
iddl
e,1
atth
esu
rfac
e.
�
The
mid
dle
axis
dete
rmin
esth
eva
lue
� .
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.45
/64
c
�
Th
eH
SV
mo
del
1.0
White
V
HS (relativ)
0.0
Blue
Cyan
Green
Yellow
Red
Magenta
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.46
/64
c
�
Th
eH
LS
mo
del
Sim
ilar
prin
cipl
eas
inth
eH
SV
mod
el.
Hu
e:A
ngle
betw
een
��
and
���� .
Lig
htn
ess:
Val
uebe
twee
n0
and
1.
Sat
ura
tio
n:
Dis
tanc
eof
aco
lour
toth
ece
ntre
(rep
rese
ntin
ggr
eyva
lues
)be
twee
n0
and
1.
For
hue:
Col
our
circ
lew
ithre
dat
�� ,yel
low
at
��� ,
gree
nat
���� ,b
lue
at����
and
viol
etat
���
� .
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.47
/64
c
�
Th
eH
LS
mo
del
SH
LWhite
black
grey axis
full
saturation
HS
L
Som
etim
esa
doub
leco
neis
pref
erre
dfo
rth
eH
LSm
odel
.T
hedo
uble
cone
refle
cts
the
fact
that
itdo
esno
tmak
ese
nse
tosp
eak
ofsa
tura
tion
for
the
colo
urs
blac
kan
dw
hite
,whe
ngr
ey-v
alue
sar
eal
read
ych
arac
teris
edby
the
lum
inan
ceva
lue.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.48
/64
c
�
Tran
sfo
rmat
ion
fro
mR
GB
toH
LS
max
=Max(R,G,B);
min
=Min(R,G,B);
L=
(max+min)/2;
if
(min==max)
{
S=0;
//H
arbitrary
return;
} mm
=max-min;
if
(L<=0.5)
S=
mm/(max+min);
else
S=
mm/(2-max-min);
r=
(R-min)/mm;
g=
(G-min)/mm;
b=
(B-min)/mm;
if
(R==max)
H=
g-b;
else
{if
(G==max)
H=
2+b-r;
else
H=
4+r-g;}
if
(H<0)
H=H+6;
H=
H*60;
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.49
/64
c
�
Per
cep
tio
n-o
rien
ted
colo
ur
mo
del
s
The
HS
Van
dth
eH
LSm
odel
belo
ngto
the
clas
sof
per
cep
tio
n-o
rien
ted
colo
ur
mo
del
ssi
nce
they
refle
ctth
ein
tuiti
vepe
rcep
tion
ofco
lour
sbe
tter.
Spe
cify
ing
the
para
met
ers
ofa
desi
red
colo
uris
easi
erw
ithpe
rcep
tion-
orie
nted
mod
els
than
with
mod
els
like
RG
Bor
CM
Y.
CN
Sis
anot
her
perc
eptio
n-or
ient
edco
lour
mod
el.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.50
/64
c
�
Th
eC
NS
mo
del
As
inH
SV
and
HLS
:Col
ours
are
defin
edby
hue
(col
our)
,sat
urat
ion
and
light
ness
.
Inst
ead
ofnu
mbe
rs,w
ords
are
used
for
the
valu
es:
Co
lou
r:pu
rple
,red
,ora
nge,
brow
n,ye
llow
,gre
en,b
lue
(with
furt
her
refin
emen
tslik
eye
llow
ish
gree
n,gr
een-
yello
w,g
reen
ish
yello
w)
Lig
htn
ess:
very
dark
,dar
k,m
ediu
m,l
ight
,ver
ylig
ht
Sat
ura
tio
n:
grey
ish,
mod
erat
e,st
rong
,viv
id
Res
tric
tion
to56
0co
mbi
natio
ns,b
utve
ryin
tuiti
ve.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.51
/64
c
�
Java
2D:
Co
lou
rm
od
els
Java
2Dsu
ppor
tsth
efo
llow
ing
colo
urm
odel
s( ColorSpace
type
s):
CIE
XY
Z:TYPEXYZ
RG
B:TYPERGB
Gre
y-va
lue
imag
es:TYPEGRAY
HS
V:TYPEHSV
CM
Y:TYPECMY
CM
YK
:TYPECMYK
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.52
/64
c
�
Java
2D:
RG
Bco
lou
rs
RG
Bco
lour
sca
nbe
defin
edw
ithth
eco
nstr
ucto
rnew
Color(
�
�
� ).
Pos
sibl
ear
gum
ents
ofth
eco
nstr
ucto
r:
�
Thr
eefloat
-val
ues
betw
een
0an
d1,
spec
ifyin
gth
ere
d,gr
een
and
blue
inte
nsity
,res
pect
ivel
y.
�
Thr
eeint
-val
ues
betw
een
0an
d25
5,sp
ecify
ing
the
red,
gree
nan
dbl
uein
tens
ity,r
espe
ctiv
ely.
�
Asi
ngleint
-val
uein
terp
rete
das
aby
teve
ctor
offo
urva
lues
.T
hree
byte
sar
eus
edfo
rR
GB
,the
four
thon
eas
aso
-cal
led
alph
a-va
lue
whi
chde
fines
how
tran
spar
entt
heco
lour
is.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.53
/64
c
�
Java
2D:
RG
Bco
lou
rs
The
met
hodg2d.setPaint(col)
sets
the
draw
ing
colo
urtocol
.
The
clas
sGradientPaint
gradPaint
=new
GradientPaint(x0,y0,colour0,
x1,y1,colour1,
repeat);
allo
ws
colo
urin
terp
olat
ion
inte
rms
ofco
lour
grad
ient
s.
�
Col
our
inte
rpol
atio
nta
kes
plac
eal
ong
the
vect
orfr
om(x0,y0)
to(x1,y1)
.
�
The
colour0
isus
edin
poin
t(x0,y0)
,the
colour1
inpo
int(x1,y1)
.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.54
/64
c
�
Java
2D:
RG
Bco
lou
rs
�
RG
B-v
alue
sar
ein
terp
olat
edal
ong
this
vect
orby
corr
espo
ndin
gco
nvex
com
bina
tions
ofcolour0
andcolour1
.(T
hesa
me
appl
ied
tove
ctor
sto
the
spec
ified
vect
or.)
�
repeat
isa
valu
eof
type
boolean
.
�
Inca
seoftrue
,the
colo
urgr
adie
ntis
repe
ated
agai
nan
dag
ain,
reve
rsin
gits
dire
ctio
nea
chtim
e.
�
Inca
seoffalse
,colour0
isus
edbe
fore
the
poin
t (x0,y0)
and
afte
r(x1,y1)
.
Use
:g2d.setPaint(gradPaint);
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.55
/64
c
�
Co
lou
rin
terp
ola
tio
n
GradientPaint
inte
rpol
ates
colo
urs
usin
gco
nvex
com
bina
tions
:
�
� ���
���
�
� ���
��
� � ��� �
� ��
�
��
�
� � ��� �
� ��
�
�
�� � �
��
Col
our
inte
rpol
atio
nfo
rte
xtur
esto
avoi
dth
etil
ing
effe
ct:
Inte
rpol
ate
atth
eed
ges,
for
inst
ance
with
afil
ter
mat
rix0.
10.
10.
10.
10.
20.
10.
10.
10.
1
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.56
/64
c
�
Co
lou
rin
terp
ola
tio
n
Inte
rpol
ated
colo
urfo
rpi
xel
� �
:
�
� ���
���
� �
������ �
�� �
� � �
� � �
neig
hbou
rof
� � �
� ����� ����
� ��
�
Inst
ead
ofa
�
�
�
filte
rm
atrix
larg
erm
atric
esca
nbe
used
.
�
Dyn
amic
filte
rm
atrix
:A
tthe
edge
,the
abov
efil
ter
mat
rixis
used
.W
ithin
crea
sing
dist
ance
toth
eed
geth
eva
lue
inth
ece
ntre
ofth
em
atrix
tend
sto
1,al
loth
erva
lues
to0.
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.57
/64
c
�
Sh
ape
and
colo
ur
inte
rpo
lati
on
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.58
/64
c
�
Sh
ape
and
colo
ur
inte
rpo
lati
on
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.59
/64
c
�
Sh
ape
and
colo
ur
inte
rpo
lati
on
�
Con
vex
com
bina
tions
ofth
eve
rtic
esof
corr
espo
ndin
gtr
iang
les
are
com
pute
dto
defin
etr
iang
ulat
ions
for
inte
rpol
ated
imag
es.
�
Eve
rypi
xel
�
has
aun
ique
repr
esen
tatio
nfo
rea
chtr
iang
lein
the
form
�
�
� ��
� �
�
� ��
� �
�
� ��
� �
whe
re
� �
�
� �
�
� �
�� �
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.60
/64
c
�
Sh
ape
and
colo
ur
inte
rpo
lati
on
�
�
lies
insi
deth
etr
iang
le
� ��
� ��
� �
ifan
don
lyif
�
can
repr
esen
ted
asa
conv
exco
mbi
natio
nof
the
vert
ices
,i.e
.
� ��
� ��
� �
�
� �
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.61
/64
c
�
Sh
ape
and
colo
ur
inte
rpo
lati
on
�
Inea
chtr
iang
leof
anin
term
edia
teim
age,
the
grey
-or
colo
urva
lue
ofa
pixe
lis
obta
ined
asth
eco
rres
pond
ing
conv
exco
mbi
natio
nof
the
corr
espo
ndin
gtw
opi
xels
inth
ein
itial
and
final
imag
e. initi
alin
term
edia
tefin
altr
iang
le
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.62
/64
c
�
Co
lou
rin
terp
ola
tio
nin
Java
2D
Rea
ding
the
colo
urof
api
xel
�
���
��
ina
BufferedImage
bi
:
int
rgbValue
=bi.getRGB(x,y);
Color
pixelColour
=new
Color(rgbValue);
Com
pute
the
RG
B-v
alue
s:int
red
=pixelColour.getRed();
int
green
=pixelColour.getGreen();
int
blue
=pixelColour.getBlue();
Com
pute
rG
raph
ics:
Are
as,t
exta
ndco
lour
s–
p.63
/64
c
�
Co
lou
rin
terp
ola
tio
nin
Java
2D
Com
pute
anin
terp
olat
edco
lour
with
RG
B-v
alue
s( rMix,
gMix,
bMix
).
Ass
ign
the
inte
rpol
ated
colo
urto
the
pixe
l
�
���
��
inth
eBufferedImage
mixedBi
:
Color
mixedColour
=new
Color(rMix,
gMix,
bMix);
mixedBi.setRGB(x,y,pixelColour.getRGB());
(see
MorphingCandS.java
and
TriangulatedImage.java
)C
ompu
ter
Gra
phic
s:A
reas
,tex
tand
colo
urs
–p.
64/6
4
